Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 6/30/2026 has been entered.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claim 10 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 10 recites “an outer wall” which renders the claim indefinite because it is unclear if this is the same or different from the outer wall recited in claim 1.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 1-4, 10, 25, 26 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hammond et al (US 3938324) in view of Shershnyov et al (US 20220003167 as referenced in OA dated 1/10/2025) in view of Fox et al (US 20130067920 as referenced in OA dated 10/24/2025)
Regarding claim 1, Hammond discloses a gas turbine engine (Column 1, lines 54-66), comprising:
a compressor section (Column 1, lines 54-66), a combustion section (Column 1, lines 54-66), and a turbine section (Column 1, lines 54-66) in serial flow arrangement, with the combustion section comprising:
a combustor liner (Figure 4; 4) that at least partially defines a combustion chamber (The combustion chamber defined by Figure 4; 4, Column 1, lines 54-66),
a gaseous fuel nozzle assembly (The gaseous fuel nozzle assembly of Figure 4 which includes at least 124, 106, 32, 36, 51, 50, 35, 19, 20. Column 4, lines 1-6) fluidly coupled with the combustion chamber, the gaseous fuel nozzle assembly comprising a fuel-air mixer (Figure 4; 32, 36, 50, 51, 35, 19, 20), a gaseous fuel passage (Figure 4; 54. Column 4, lines 1-6) fluidly coupled with the fuel-air mixer, and an air passage (The air passage between Figure 4; 32 and 16) fluidly coupled with the fuel-air mixer,
wherein the fuel-air mixer includes a plurality of vanes (Figure 4; 36, 35),
wherein at least one vane of the plurality of vanes is disposed at least partially at an angle relative to an axial direction (The angle of Figure 4; 35 or 36 with respect to the axial direction),
wherein each vane of the plurality of vanes includes a first radial section (Figure 4; 36), a second radial section (Figure 4; 35) extending radially outward from the first radial section,
wherein the fuel-air mixer further includes an intermediate wall (Figure 4; 50, 51),
wherein the intermediate wall defines a first annular space (The annular space between Figure 4; 50 and 19) between the intermediate wall and an outer wall (Figure 4; 19, 20) and a second annular space (The annular space between Figure 4; 32, 51) between the intermediate wall and an inner wall (Figure 4; 32),
wherein the intermediate wall is configured to split air from the air passage between the first annular space and the second annular space (Functional Language, the intermediate wall splits air from the air passage between the first and second annular space), and
wherein the intermediate wall includes an aft end (The right end of the intermediate wall in Figure 4) that extends axially aft of an aft end (The right end of Figure 4; 32 which is 124) of the inner wall and into a premixing chamber (The premixing chamber between the aft end of the intermediate wall and the outer wall) defined at least in part by the outer wall, the aft end of the intermediate wall being angled radially inward to generate radially inward flow momentum away from the outer wall (Functional Language, the intermediate wall is angled radially inward and generates radially inward flow momentum away from the outer wall) .
Hammond does not disclose wherein the angle varies in a radial direction,
wherein each vane of the plurality of vanes includes a first radial section, a second radial section extending radially outward from the first radial section, and a third radial section extending radially outward from the second radial section,
wherein the angle is larger for the second radial sections than for the first radial sections and the third radial sections,
wherein the fuel-air mixer further includes an intermediate wall having a lobed cross- sectional shape configured to enhance turbulence and spread a flow of turbulent air radially and laterally outward,
However, Shershnyov teaches a gas turbine engine (Figure 1; 1000), comprising:
a compressor section (Figure 1; 1100), a combustion section (Figure 1; 1200), and a turbine section (Figure 1; 1300) in serial flow arrangement, with the combustion section comprising:
a combustor liner (Figure 2; 1251) that at least partially defines a combustion chamber (Figure 2; 1240); and
a gaseous fuel nozzle assembly (Figure 3; 1400. Paragraph 0005, 0056) fluidly coupled with the combustion chamber, the gaseous fuel nozzle assembly comprising a fuel-air mixer (Figure 9; 1600), a gaseous fuel passage (Figure 4; 1654, 1673, 1653, 1672, 1652, 1671, 1651) fluidly coupled with the fuel-air mixer, and an air passage (The passage between Figure 3; 1410 and 1420 upstream of 1600) fluidly coupled with the fuel-air mixer;
wherein the fuel-air mixer includes a plurality of vanes (In Figure 9; the instance of 1623, 1613, the instance of 1622, 1612, and the instance of 1621);
wherein at least one vane of the plurality of vanes is disposed at least partially at an angle (Figure 10; A11, A13, A12) relative to an axial direction (The axial direction along a centerline of Figure 3; 1400);
wherein the angle varies in a radial direction (The radial direction along a centerline of Figure 3; 1400);
wherein each vane of the plurality of vanes includes a first radial section (Figure 4; 1621), a second radial section (Figure 4; 1612, 1622, 1613) extending radially outward from the first radial section, and a third radial section (Figure 4; 1623) extending radially outward from the second radial section;
wherein the angle is larger for the second radial sections than for the first radial sections and the third radial sections;
wherein the fuel-air mixer further includes an intermediate wall (Figure 9; 1613);
wherein the intermediate wall defines a first annular space (The annular space between Figure 4; 1613 and 1614, see Figure 9) between the intermediate wall and an outer wall (Figure 4; 1614) and a second annular space (The annular space between Figure 4; 1613 and 1612, see Figure 9) between the intermediate wall and an inner wall (Figure 4; 1612), and
wherein the intermediate wall is configured to split air from the air passage between the first annular space and the second annular space (Functional Language, the intermediate wall splits air between the first and second annular space).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond wherein the angle varies in a radial direction, wherein each vane of the plurality of vanes includes a first radial section, a second radial section extending radially outward from the first radial section, and a third radial section extending radially outward from the second radial section, wherein the angle is larger for the second radial sections than for the first radial sections and the third radial sections as taught by and suggested by Shershnyov in order to improve mixing efficiency (Paragraph 0100) and easily mix fuels (Paragraph 0113, the modification has three rings of vanes each with a different angle and has the vanes having fuel ports).
Hammond in view of Shershnyov does not teach wherein the fuel-air mixer further includes an intermediate wall having a lobed cross- sectional shape configured to enhance turbulence and spread a flow of turbulent air radially and laterally outward.
However, Fox teaches wherein a fuel-air mixer (Figure 3) further includes an intermediate wall (Figure 4; 44 which has 52) having a lobed cross- sectional shape (The lobed cross-sectional shape of Figure 4; 52) configured to enhance turbulence and spread a flow of turbulent air radially and laterally outward (Functional Language, the lobed shape enhances turbulence and spreads a flow of turbulent air radially and laterally outward).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond in view of Shershnyov wherein the fuel-air mixer further includes an intermediate wall having a lobed cross- sectional shape configured to enhance turbulence and spread a flow of turbulent air radially and laterally outward as taught by and suggested by Fox in order to provide very good mixing (Paragraph 0040, the modification adds a lobed mixer to each intermediate wall).
Regarding claim 2, Hammond in view of Shershnyov and Fox teaches the invention as claimed.
Hammond does not disclose wherein the angle is in a first range of 0 degrees to 40 degrees, inclusive of end points, for the first radial section of the plurality of vanes.
However, Shershnyov teaches wherein the angle is in a first range of 0 degrees to 40 degrees (Paragraph 0100, The first angle is 23 degrees), inclusive of end points, for the first radial section of the plurality of vanes.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond wherein the angle is in a first range of 0 degrees to 40 degrees, inclusive of end points, for the first radial section of the plurality of vanes as taught by and suggested by Shershnyov in order to improve mixing efficiency (Paragraph 0100) and easily mix fuels (Paragraph 0113, this is the same modification as claim 1).
Regarding claim 3, Hammond in view of Shershnyov and Fox teaches the invention as claimed.
Hammond does not disclose wherein the angle is in a second range of 40 degrees to 80 degrees, inclusive of end points, for the second radial section of the plurality of vanes.
However, Shershnyov teaches wherein the angle is in a second range of 40 degrees to 80 degrees (Paragraph 0100, The second angle is 46 degrees), inclusive of end points, for the second radial section of the plurality of vanes.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond wherein the angle is in a second range of 40 degrees to 80 degrees, inclusive of end points, for the second radial section of the plurality of vanes as taught by and suggested by Shershnyov in order to improve mixing efficiency (Paragraph 0100) and easily mix fuels (Paragraph 0113, this is the same modification as claim 1).
Regarding claim 4, Hammond in view of Shershnyov and Fox teaches the invention as claimed.
Hammond does not disclose wherein the angle is in a third range of 0 degrees to 40 degrees, inclusive of end points, for the third radial section of the plurality of vanes.
However, Shershnyov teaches wherein the angle is in a third range of 0 degrees to 40 degrees (Paragraph 0100, The second angle is 40 degrees), inclusive of end points, for the third radial of the plurality of vanes.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond wherein the angle is in a third range of 0 degrees to 40 degrees, inclusive of end points, for the third radial section of the plurality of vanes as taught by and suggested by Shershnyov in order to improve mixing efficiency (Paragraph 0100) and easily mix fuels (Paragraph 0113, this is the same modification as claim 1).
Regarding claim 10, Hammond in view of Shershnyov and Fox teaches the invention as claimed.
Hammond does not disclose wherein the fuel-air mixer includes an outer wall, a core region, and an intermediate region; and
wherein the plurality of vanes is configured to facilitate increased fluid velocity in the axial direction adjacent the outer wall and in the core region, and are configured to facilitate increased fluid velocity in a tangential direction in the intermediate region.
However, Shershnyov teaches wherein the fuel-air mixer includes an outer wall (The portion of Figure 3; 1420 contacting and downstream of 1600), a core region (The region at and downstream of Figure 4; 1621), and an intermediate region (The region at and downstream of Figure 4; 1612, 1622, 1613); and
wherein the plurality of vanes is configured to facilitate increased fluid velocity in the axial direction adjacent the outer wall and in the core region (Functional Language, Figure 10 shows 1621, 1623 having a smaller angle than 1622, so that these produce an increased fluid velocity in the axial direction as compared to 1622), and are configured to facilitate increased fluid velocity in a tangential direction (The tangential direction with respect to the centerline of Figure 3; 1400) in the intermediate region (Functional Language, Figure 10 shows 1621, 1623 having a smaller angle than 1622, so that 1622 produces increased fluid velocity in a tangential direction as compared to 1621, 1623).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond wherein the fuel-air mixer includes an outer wall, a core region, and an intermediate region; and wherein the plurality of vanes is configured to facilitate increased fluid velocity in the axial direction adjacent the outer wall and in the core region, and are configured to facilitate increased fluid velocity in a tangential direction in the intermediate region as taught by and suggested by Shershnyov in order to improve mixing efficiency (Paragraph 0100) and easily mix fuels (Paragraph 0113, this is the same modification as claim 1).
Regarding claim 25, Hammond in view of Shershnyov and Fox teaches the invention as claimed.
Hammond does not disclose wherein an angle variation is configured to produce a radial velocity gradient across the fuel-air mixer; and
wherein the angle variation is configured to increase axial velocity in an inner radial region and an outer radial region of the premixing chamber, and to increase tangential velocity in an intermediate radial region of the premixing chamber.
However, Shershnyov teaches wherein an angle variation (The radial angle variation of the vanes) is configured to produce a radial velocity gradient (Functional Language, The radial velocity gradient produced by the vanes) across the fuel-air mixer; and
wherein the angle variation is configured to increase axial velocity (Functional Language, Figure 10 shows 1621, 1623 having a smaller angle than 1622, so that these produce an increased fluid velocity in the axial direction as compared to 1622) in an inner radial region (The region where the innermost vanes are located) and an outer radial region (The region where the outermost vanes are located) of a premixing chamber (The portion of Figure 3; 1420 downstream of 1600), and to increase tangential velocity (Functional Language, Figure 10 shows 1621, 1623 having a smaller angle than 1622, so that 1622 produces increased fluid velocity in a tangential direction as compared to 1621, 1623 ) in an intermediate radial region (The region between the innermost and outermost vanes are located) of the premixing chamber.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond wherein an angle variation is configured to produce a radial velocity gradient across the fuel-air mixer; and wherein the angle variation is configured to increase axial velocity in an inner radial region and an outer radial region of the premixing chamber, and to increase tangential velocity in an intermediate radial region of the premixing chamber as taught by and suggested by Shershnyov in order to improve mixing efficiency (Paragraph 0100) and easily mix fuels (Paragraph 0113, this is the same modification as claim 1).
Regarding claim 26, Hammond in view of Shershnyov and Fox teaches the invention as claimed.
Hammond further discloses wherein the fuel-air mixer further includes a set of fuel orifices (Figure 4; 64) configured to emit fuel (The fuel from Figure 4; 64) aft of the second radial sections of the plurality of vanes such that fuel is dispersed into a stream of turbulent air (Functional language, the set of fuel orifices is dispersed into a stream of turbulent air from the plurality of vanes).
Claim(s) 5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hammond in view of Shershnyov and Fox as applied to claim 4 above, and further in view of Schmotolocha et al (US 20040050061 as referenced in OA dated 5/21/2025)
Regarding claim 5, Hammond in view of Shershnyov and Fox teaches the invention as claimed.
Hammond does not disclose wherein the gaseous fuel nozzle assembly comprises fuel posts extending from the second radial sections.
However, Shershnyov teaches wherein the gaseous fuel nozzle assembly comprises fuel holes (Figure 8; 1640) extending from the second radial sections.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond wherein the gaseous fuel nozzle assembly comprises fuel posts extending from the second radial sections as taught by and suggested by Shershnyov in order to improve mixing efficiency (Paragraph 0100) and easily mix fuels (Paragraph 0113, this is the same modification as claim 1).
Hammond in view of Shershnyov and Fox does not teach fuel posts.
However, Schmotolocha teaches a plurality of vanes (Figure 4; 402) each include a first radial section (The radially inner third of Figure 4; 402), a second radial section (The radially middle third of Figure 4; 402) extending radially outward from the first radial section, and a third radial section (The radially outer third of Figure 4; 402) extending radially outward from the second radial section;
a gaseous fuel nozzle assembly (Figure 4; 30, Paragraph 0062) comprises fuel posts (Figure 21; 1050, 1000h) extending from the second radial sections (Figure 18 shows fuel injected into radially inner third section, radially middle third section, and radially outer third section. Paragraph 0106-0108 states Figure 21-22 are similar to Figure 18, so that Figure 21; 1050 and 1000h would also be in the second radial sections).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond in view of Shershnyov and Fox to include fuel posts as taught by and suggested by Schmotolocha in order to provide highly controlled fine scale mixing (Paragraph 0108, The modification has the vanes having the fuel posts of Schmotolocha).
Claim(s) 6-9, 11, 13, 17-21 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hammond in view of Angel et al (US 6141967 as referenced in OA dated 1/10/2025) and ELKady et al (US 20080163627 as referenced in OA dated 4/8/2026)
Regarding claim 13, Hammond discloses a gaseous fuel nozzle assembly (The gaseous fuel nozzle assembly of Figure 4 which includes at least 124, 106, 32, 36, 51, 50, 35, 19, 20. Column 4, lines 1-6) for a gas turbine engine (Column 1, lines 54-66), the gaseous fuel nozzle assembly comprising:
a fuel-air mixer (Figure 4; 32, 36, 50, 51, 35, 19, 20),
a gaseous fuel conduit (Figure 4; 54. Column 4, lines 1-6) fluidly coupled with the fuel-air mixer,
an air passage (The air passage between Figure 4; 32 and 16) fluidly coupled with the fuel-air mixer,
wherein the fuel-air mixer includes a plurality of vanes (Figure 4; 36, 35) each disposed at an angle relative to an axial direction (The angle of Figure 4; 35 or 36 with respect to the axial direction),
wherein the fuel-air mixer includes an inner wall (Figure 4; 32) and an outer wall (Figure 4; 19, 20), the outer wall having a converging configuration (The outer wall has a converging configuration),
wherein the fuel-air mixer includes an intermediate wall (Figure 4; 50, 51) disposed at least partially between the inner wall and the outer wall,
wherein the intermediate wall includes an aft end (The right end of the intermediate wall in Figure 4) with an inner radial surface (The radially inner surface of Figure 4; 51) that converges toward a centerline (The centerline of the fuel-air mixer) of the fuel-air mixer,
wherein the aft end of the intermediate wall extends axially aft of an aft end of the inner wall and into a premixing chamber defined at least in part by the outer wall, the aft end of the intermediate wall being angled radially inward to generate radially inward flow momentum away from the outer wall.
wherein the aft end of the intermediate wall extends axially aft of an aft end (The right end of Figure 4; 32 which is 124) of the inner wall and into a premixing chamber (The premixing chamber between the aft end of the intermediate wall and the outer wall) defined at least in part by the outer wall, the aft end of the intermediate wall being angled radially inward to generate radially inward flow momentum away from the outer wall (Functional Language, the intermediate wall is angled radially inward and generates radially inward flow momentum away from the outer wall).
Hammond does not disclose wherein the angle varies in a radial direction;
wherein the gaseous fuel conduit supplies a diatomic hydrogen fuel without diluent to the fuel-air mixer.
However, Angel teaches a gaseous fuel nozzle assembly (Figure 2) for a gas turbine engine (The gas turbine engine in the abstract), the gaseous fuel nozzle assembly comprising:
a fuel-air mixer (Figure 2; 24),
an air passage (The air passage between Figure 1; 40 and 42) fluidly coupled with the fuel-air mixer;
wherein the fuel-air mixer includes a plurality of vanes (Figure 1; 28); each disposed at an angle relative to an axial direction (The angle of each vane relative to the axial direction of the central axis of Figure 1; 24); and
wherein the angle (Figure 8A and 8B) varies in a radial direction (The radial direction of the central axis of Figure 1; 24);
wherein the fuel-air mixer includes an inner wall (Figure 1; 42) and an outer wall (Figure 1; 40), the outer wall having a converging configuration;
wherein the fuel-air mixer includes an intermediate wall (Figure 1; 30) disposed at least partially between the inner wall and the outer wall;
wherein the intermediate wall includes an aft end (The aft end of the intermediate wall) with an inner radial surface (The inner radial surface of the aft end); and
a centerline (The centerline of the fuel-air mixer)of the fuel-air mixer.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond wherein the angle varies in a radial direction as taught by and suggested by Angel in order to provide a boundary layer (Column 5, lines 53-58. The modification uses the outer vane shape of Angel in Hammond. This includes having the outer vanes of Angel extending to the aft end of the intermediate wall).
Hammond in view of Angel does not teach wherein the gaseous fuel conduit supplies a diatomic hydrogen fuel without diluent to the fuel-air mixer.
However, ELKady teaches wherein a gaseous fuel conduit (The conduits feeding Figure 5; 112 in Paragraph 0033) supplies a diatomic hydrogen fuel (The pure hydrogen in Paragraph 0038, 0046) without diluent (The hydrogen being pure fuel does not include diluent) to a fuel-air mixer (Figure 5; 90, Paragraph 0033).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond in view of Angel wherein the gaseous fuel conduit supplies a diatomic hydrogen fuel without diluent to the fuel-air mixer as taught by and suggested by ELKady in order to provide enhanced fuel flexibility (Paragraph 0053, the modification allows the combustor to run a variety of fuel including pure hydrogen).
Regarding claim 6, Hammond in view of Angel and ELKady teaches the invention as claimed.
Hammond further discloses wherein the plurality of vanes is a first plurality of vanes (Figure 4; 35), and the fuel-air mixer further comprises a second plurality of vanes (Figure 4; 36) disposed radially inward of the first plurality of vanes.
Regarding claim 7, Hammond in view of Angel and ELKady teaches the invention as claimed.
Hammond does not disclose wherein the second plurality of vanes includes a second vane first radial section and a second vane second radial section disposed at different angles relative to the axial direction.
However, Angel teaches wherein the plurality of vanes is a first plurality of vanes (Figure 2; 28), and the fuel-air mixer further comprises a second plurality of vanes (Figure 2; 26) disposed radially inward of the first plurality of vanes;
wherein the second plurality of vanes includes a second vane first radial section (Figure 4; 72) and a second vane second radial section (Figure 4; 70) disposed at different angles (Figure 5A and 5B show different angles) relative to the axial direction.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond wherein the second plurality of vanes includes a second vane first radial section and a second vane second radial section disposed at different angles relative to the axial direction as taught by and suggested by Angel in order to provide a boundary layer (Column 5, lines 53-58. This is the same modification as claim 13).
Regarding claim 8, Hammond in view of Angel and ELKady teaches the invention as claimed.
Hammond further discloses wherein the first plurality of vanes extends from the intermediate wall to the outer wall; and
wherein the second plurality of vanes extends from the intermediate wall to the inner wall.
Regarding claim 9, Hammond in view of Angel and ELKady teaches the invention as claimed.
Hammond further discloses wherein the intermediate wall includes an intermediate wall fuel orifice (Figure 4; 55) and an intermediate wall fuel passage (Figure 4; 54) fluidly coupled with the intermediate wall fuel orifice.
Regarding claim 11, Hammond in view of Angel and ELKady teaches the invention as claimed.
Hammond further discloses wherein the plurality of vanes is a first plurality of vanes (Figure 4; 35);
wherein the fuel-air mixer further comprises a second plurality of vanes (Figure 4; 36) disposed radially inward of the first plurality of vanes.
Hammond does not disclose wherein the first plurality of vanes includes a first vane first radial section and a first vane second radial section radially inward of the first vane first radial section;
wherein the second plurality of vanes includes a second vane first radial section and a second vane second radial section disposed radially outward of the second vane first radial section; and
wherein the first vane first radial section and the second vane first radial section are angled relative to the axial direction less than the first vane second radial section and the second vane second radial section to facilitate higher axial fluid velocity; and
wherein the first vane second radial section and the second vane second radial section are configured to facilitate higher tangential fluid velocity compared to the first vane first radial section and the second vane first radial section.
However, Angel teaches wherein the plurality of vanes is a first plurality of vanes (Figure 2; 28);
wherein the fuel-air mixer further comprises a second plurality of vanes (Figure 2; 26) disposed radially inward of the first plurality of vanes;
wherein the first plurality of vanes includes a first vane first radial section (Figure 8A; 86) and a first vane second radial section (Figure 8B; 88) radially inward of the first vane first radial section;
wherein the second plurality of vanes includes a second vane first radial section (Figure 5A; 72) and a second vane second radial section (Figure 5B; 70) disposed radially outward of the second vane first radial section; and
wherein the first vane first radial section and the second vane first radial section are angled relative to the axial direction less than the first vane second radial section and the second vane second radial section to facilitate higher axial fluid velocity (Functional Language, Figure 5A, 5B, 8A, 8B show the first vane first radial section and the second vane first radial section having a higher axial fluid velocity); and
wherein the first vane second radial section and the second vane second radial section are configured to facilitate higher tangential fluid velocity compared to the first vane first radial section and the second vane first radial section Functional Language, Figure 5A, 5B, 8A, 8B show the first vane second radial section and the second vane second radial section having a higher tangential fluid velocity)
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond wherein the first plurality of vanes includes a first vane first radial section and a first vane second radial section radially inward of the first vane first radial section; wherein the second plurality of vanes includes a second vane first radial section and a second vane second radial section disposed radially outward of the second vane first radial section; and wherein the first vane first radial section and the second vane first radial section are angled relative to the axial direction less than the first vane second radial section and the second vane second radial section to facilitate higher axial fluid velocity; and wherein the first vane second radial section and the second vane second radial section are configured to facilitate higher tangential fluid velocity compared to the first vane first radial section and the second vane first radial section as taught by and suggested by Angel in order to provide a boundary layer (Column 5, lines 53-58. This is the same modification as claim 13).
Regarding claim 17, Hammond in view of Angel and ELKady teaches the invention as claimed.
Hammond further discloses wherein the intermediate wall includes an outer radial surface (The radially outer surface of Figure 4; 50), the inner radial surface, a trailing edge (The trailing edge of the intermediate wall), and a set of intermediate wall fuel orifices (Figure 4; 55).
Regarding claim 19, Hammond in view of Angel and ELKady teaches the invention as claimed.
Hammond further discloses wherein the set of intermediate wall fuel orifices includes intermediate wall orifices (Figure 4; 55) at the inner radial surface.
Regarding claim 21, Hammond in view of Angel and ELKady teaches the invention as claimed.
Hammond further discloses wherein the plurality of vanes is a first plurality of vanes (Figure 4; 35) extending between the outer wall and the intermediate wall;
wherein the fuel-air mixer includes a second plurality of vanes (Figure 4; 36) extending between the intermediate wall and the inner wall; and
wherein the first plurality of vanes extend into an annular space (The annular space between the outer wall and intermediate wall) between the outer wall and the intermediate wall.
Hammond does not disclose wherein the first plurality of vanes extend into an annular space between the outer wall and the aft end of the intermediate wall.
However, Angel teaches wherein the plurality of vanes is a first plurality of vanes (Figure 1; 28) extending between the outer wall and the intermediate wall;
wherein the fuel-air mixer includes a second plurality of vanes (Figure 1; 26) extending between the intermediate wall and the inner wall; and
wherein the first plurality of vanes extend into an annular space (The annular space between the outer wall and aft end) between the outer wall and the aft end of the intermediate wall
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond wherein the first plurality of vanes extend into an annular space between the outer wall and the aft end of the intermediate wall as taught by and suggested by Angel in order to provide a boundary layer (Column 5, lines 53-58. This is the same modification as claim 13).
Claim(s) 18, 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hammond in view of Angel and ELKady as applied to claim 17 above, and further in view of Venkatesan et al (US 20160033132 as referenced in OA dated 4/8/2026).
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Annotated Figure 6 of Venkatesan et al (US 20160033132)
Regarding claim 18, Hammond in view of Angel and ELKady teaches the invention as claimed.
Hammond in view of Angel and ELKady does not teach wherein the set of intermediate wall fuel orifices includes intermediate wall orifices at the outer radial surface.
However, Venkatesan teaches a gaseous fuel nozzle assembly (Figure 6) for a gas turbine engine (Figure 1; 10), the gaseous fuel nozzle assembly comprising:
a fuel-air mixer (Figure 6; 130),
a gaseous fuel conduit (The conduit supplying fuel to Figure 6; 90. Paragraph 0006) fluidly coupled with the fuel-air mixer, and
an air passage (Figure 6; 102) fluidly coupled with the fuel-air mixer;
wherein the fuel-air mixer includes a plurality of vanes (Annotated Figure 6; labeled second vanes) each disposed at an angle relative to an axial direction (The angle of each vane with respect to the centerline depicted as a dashed-dotted line in Figure 6);
wherein the fuel-air mixer includes an inner wall (Annotated Figure 6; labeled inner wall) and an outer wall (Figure 6; 84), the outer wall having a converging configuration (The outer wall has a converging configuration);
wherein the fuel-air mixer includes an intermediate wall (Annotated Figure 6; labeled intermediate wall) disposed at least partially between the inner wall and the outer wall;
wherein the intermediate wall includes an aft end (The tapered portion of the intermediate wall is an aft end) with an inner radial surface (Annotated Figure 6; labeled inner radial surface) and a centerline (The dashed dotted centerline axis of Figure 6) of the fuel-air mixer;
wherein the intermediate wall includes an outer radial surface (Annotated Figure 6; labeled outer radial surface), the inner radial surface, a trailing edge (Annotated Figure 6; labeled trailing edge), and a set of intermediate wall fuel orifices (Figure 6; 114, 122);
wherein the set of intermediate wall fuel orifices includes intermediate wall orifices at the outer radial surface (There are instance of Figure 6; 114 on the outer radial surface).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond in view of Angel and ELKady wherein the set of intermediate wall fuel orifices includes intermediate wall orifices at the outer radial surface as taught by and suggested by Venkatesan in order to reduce the potential for fuel wetting (Paragraph 0035, The modification uses the arrangement of fuel orifices of Venkatesan in Hammond).
Regarding claim 20, Hammond in view of Angel and ELKady teaches the invention as claimed.
Hammond in view of Angel and ELKady does not teach wherein the set of intermediate wall fuel orifices includes intermediate wall orifices at the trailing edge.
However, Venkatesan teaches a gaseous fuel nozzle assembly (Figure 6) for a gas turbine engine (Figure 1; 10), the gaseous fuel nozzle assembly comprising:
a fuel-air mixer (Figure 6; 130),
a gaseous fuel conduit (The conduit supplying fuel to Figure 6; 90. Paragraph 0006) fluidly coupled with the fuel-air mixer, and
an air passage (Figure 6; 102) fluidly coupled with the fuel-air mixer;
wherein the fuel-air mixer includes a plurality of vanes (Annotated Figure 6; labeled second vanes) each disposed at an angle relative to an axial direction (The angle of each vane with respect to the centerline depicted as a dashed-dotted line in Figure 6);
wherein the fuel-air mixer includes an inner wall (Annotated Figure 6; labeled inner wall) and an outer wall (Figure 6; 84), the outer wall having a converging configuration (The outer wall has a converging configuration);
wherein the fuel-air mixer includes an intermediate wall (Annotated Figure 6; labeled intermediate wall) disposed at least partially between the inner wall and the outer wall;
wherein the intermediate wall includes an aft end (The tapered portion of the intermediate wall is an aft end) with an inner radial surface (Annotated Figure 6; labeled inner radial surface) and a centerline (The dashed dotted centerline axis of Figure 6) of the fuel-air mixer;
wherein the intermediate wall includes an outer radial surface (Annotated Figure 6; labeled outer radial surface), the inner radial surface, a trailing edge (Annotated Figure 6; labeled trailing edge), and a set of intermediate wall fuel orifices (Figure 6; 114, 122);
wherein the set of intermediate wall fuel orifices includes intermediate wall orifices at the trailing edge (Figure 6; 122 is at the trailing edge).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond in view of Angel and ELKady wherein the set of intermediate wall fuel orifices includes intermediate wall orifices at the trailing edge as taught by and suggested by Venkatesan in order to reduce the potential for fuel wetting (Paragraph 0035, The modification uses the arrangement of fuel orifices of Venkatesan in Hammond).
Claim(s) 22 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hammond in view of Angel and ELKady as applied to claim 21 above, and further in view of Twardochleb et al (US 20120324900 as referenced in OA dated 10/24/2025)
Regarding claim 22, Hammond in view of Angel and ELKady teaches the invention as claimed.
Hammond in view of Angel and ELKady does not teach a perforated plate upstream of at least one of the first plurality of vanes or the second plurality of vanes.
However, Twardochleb teaches a perforated plate (Figure 2A; 60) upstream of a plurality of vanes (Figure 2A; 54).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond in view of Angel and ELKady to include a perforated plate upstream of at least one of the plurality of vanes (In the context of Hammond in view of Angel and ELKady, the perforated plate is upstream of both the first and second plurality of vanes) as taught by and suggested by Twardochleb in order to control the amount of air entering (Paragraph 0015, The modification adds a perforated plate upstream of the first and second plurality of vanes).
Claim(s) 23-24 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hammond in view of Angel and ELKady as applied to claim 21, 11, and further in view of Schmotolocha.
Regarding claim 23, Hammond in view of Angel and ELKady teaches the invention as claimed.
Hammond in view of Angel and ELKady does not teach a plurality of fuel posts aligned with the first vane second radial section.
However, Schmotolocha teaches a first plurality of vanes (Figure 4; 402) includes a first vane first radial section (The radially outer half of Figure 4; 402) and a first vane second radial section (The radially inner half of Figure 4; 402) radially inward of the first vane first radial section;
a plurality of fuel posts (Figure 21; 1050, 1000h) aligned with the first vane second radial section (Figure 18 shows fuel injected into radially inner section, radially middle section, and radially outer section. Paragraph 0106-0108 states Figure 21-22 are similar to Figure 18, so that Figure 21; 1050 and 1000h would also be in the first vane second radial section).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond in view of Angel and ELKady to include a plurality of fuel posts aligned with the first vane second radial section as taught by and suggested by Schmotolocha in order to provide highly controlled fine scale mixing (Paragraph 0108, The modification has the vanes having the fuel posts of Schmotolocha)
Regarding claim 24, Hammond in view of Angel and ELKady and Schmotolocha teaches the invention as claimed.
Hammond in view of Angel and ELKady does not teach wherein the plurality of fuel posts have a tangential configuration.
However, Schmotolocha teaches wherein the plurality of fuel posts have a tangential configuration (Figure 3 shows the trailing edges of the vanes being oriented, at least partially in the tangential direction, so that at least some Figure 21; 1000h have a tangential configuration).
Therefore, it would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the invention of Hammond in view of Angel and ELKady wherein the plurality of fuel posts have a tangential configuration as taught by and suggested by Schmotolocha in order to provide highly controlled fine scale mixing (Paragraph 0108, This is the same modification as claim 23)
Response to Arguments
Applicant’s arguments with respect to claim(s) 1, 13 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Conclusion
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/EDWIN KANG/Primary Examiner, Art Unit 3741
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